CN200997422Y - Ultra-thin bent polymer lithium-ion battery - Google Patents

Abstract

The utility model relates to an ultra-thin bendable battery with the macromolecule lithium ion and is characterized in that the battery mainly comprises four kinds of composite elements: the 1A negative electrode composite element that is provided in the metal copper foil surface with a negative electrode coating to form the negative electrode plate and has the nickel ear wrapped by the CPP leakage-prevention film as the cathode leading wire; the 1B positive electrode composite element that is provided in the metal copper foil surface with a positive electrode coating to form the positive electrode plate and has the nickel ear wrapped by the CPP leakage-prevention film as the anode leading wire; the 1C electrolyte composite element that is provided with a gel electrolyte layer at the two sides of the polyethylene-propylene diaphragm; the gel electrolyte layer agglutinates the negative electrode composite element and the positive electrode composite element respectively to the two sides of the polyethylene-propylene diaphragm; and the 1D casing that is an aluminum composite diaphragm casing composed of layers of polyethylene diaphragm + aluminum foil + polypropylene diaphragm + polyamide diaphragm; wherein the negative electrode composite element, the positive electrode composite element and the electrolyte composite element jointly constitute the battery core and the casing wraps the battery core.

Description

A kind of ultrathin type, flexible macromolecule lithium ion battery

Technical field

The utility model relates to a kind of lithium ion battery, relates in particular to a kind of ultrathin type, flexible macromolecule lithium ion battery, or is called polymer Li-ion battery.This battery is charging and discharging repeatedly, repeatedly recycles.

Background technology

The metallic shell lithium-ion battery that uses stainless steel or aluminum metal case from nineteen ninety come out and large-scale production in 1993 since, with other battery (NI-G and Ni-MH battery) incomparable excellent performance and many market segments have been captured in fast development rapidly.In the whole world in tens billion of dollars the digital battery product market, the metallic shell lithium-ion battery has been widely used in mobile phone, notebook computer, laptop computer, personal digital assistant, Digital Video, digital camera, portable DVD player/VCD/CD and MP3 player etc. as high-tech new forms of energy product, become various modern device for mobile communication and the indispensable parts of electronic equipment, in moving, be engaged in for example office of various commercial activitys, communication, management, control and in moving amusement many convenience are provided.But along with the renewal and the development of technology, have higher requirement to portable power source in market, for example thinner, lighter, arbitrary shape, more high-energy-density, safer and low price etc. more.The square metal case lithium ion battery is owing to the self structure characteristics, and the thickness of its battery can not be less than 1 millimeter, more impossible flexural deformation.The product blank appears in ultrathin and flexible battery applications field.

Under the promotion of the market demand, use aluminum-plastic composite membrane to arise at the historic moment as the flexible packing lithium ion battery of shell, improved safety issues such as on fire and blast have taken place in the lithium ion battery use.Yet, from technical performance, when existing flexible packing lithium ion battery is used, there is following defective in ultrathin and flexible field of batteries:

(1) uses liquid electrolyte in the flexible packing lithium ion battery, be present in the electrolyte between positive, negative electrode plate and the barrier film, make these three cell devices be in loose and state no bonding force.When variation of ambient temperature, volumetric expansion takes place in electrolyte easily, even gasification, causes the inside battery structural thickness sharply to increase, and positive, negative electrode plate separates with the barrier film three.Because what the shell of flexible packing lithium ion battery used is not rigid metallic material, but soft aluminum-plastic composite membrane, the rapid increase of this inside battery structural thickness, under the restriction that does not have outer rigid housing, directly the increase with cell integrated thickness reflects, cause obviously exceeding standard of battery overall dimension, surpass several times even tens times of technical requirement, stock's battery is scrapped because of assembling, be assemblied in the battery in the mobile device, may have damaged components and parts on every side because of volume of battery expands.

(2) these three cell devices of positive, negative electrode plate and barrier film expand at the electrolyte volume, and when the three separated, a series of electrochemical properties of battery will variation.For example, the internal resistance of cell increases, and discharge capacity reduces, and cycle life reduces, and every function of battery will fail rapidly and lose efficacy.

(3) surface area of slimline battery is bigger, is subjected to extraneous impact and damage easily.Use the flexible packing lithium ion battery of electrolyte to occur the phenomenon of leakage easily, the components and parts around the battery are produced chemical corrosion.

Therefore, metallic shell lithium-ion battery and flexible packing lithium ion battery all can not satisfy ultrathin and flexible demand.

The utility model content

The purpose of this utility model is to overcome the deficiencies in the prior art, a kind of ultrathin type, flexible macromolecule lithium ion battery are provided, in the normal serviceability temperature scope of digital mobile device, the varied in thickness of battery is minimum, not only can be ultrathin, and, can be crooked, to adapt to the variation of profile in use of ultrathin digital mobile device.

The purpose of this utility model is achieved by the following technical programs:

A kind of ultrathin type, flexible macromolecule lithium ion battery, it mainly is made of four kinds of composite components:

1a, negative electrode composite component, it has the negative electrode coating to constitute negative electrode plate in the metal copper foil surface coated, and the nickel lug that coats with the CPP leakproof film is a negative wire;

1b, positive electrode composite component, it has the positive electrode coating to constitute electrode film in the metal aluminum foil surface coated, and the aluminium pole ears that coats with the CPP leakproof film is a positive wire;

1c, electrolyte composite component, it is provided with the gel state electrolyte layer in polyethylene-propylene barrier film both side surface, and described gel state electrolyte layer is bonded in the PE-PP membrane two sides respectively with negative electrode composite component and positive electrode composite component;

1d, shell, the aluminum-plastic composite membrane shell of forming by multilayer polyethylene film+aluminium foil+polypropylene screen+polyamide membrane;

Wherein, described negative electrode composite component, positive electrode composite component and electrolyte composite component constitute battery jointly, and described shell wraps described battery.

Key of the present utility model is to have adopted the gel state electrolyte layer, provide process in the patent of invention (patent No. is ZL02108832.2) that specifically is to use the applicant to obtain the authorization, preparation gel state electrolyte layer between positive, negative electrode plate and barrier film, be solidified togather the three is bonding, form an integral body, not only can effectively overcome the problem of flexible packing lithium ion battery change in volume, particularly thickness swelling, and reach the purpose that prevents battery leakage, so that guarantee the technical performance and the profile index of battery effectively.

Described negative electrode coating is made of active matter, conductive agent, binding agent, and active matter comprises inorganic material for example carbon dust, carbon fiber, graphite powder and graphite fibre etc., and metal alloy is for example tin-based oxide and silicon-base oxide of lithium alloy and metal oxide for example.

Described positive electrode coating is made of active matter, conductive agent, binding agent, and active matter comprises inorganic material for example cobalt acid lithium, lithium nickelate, LiMn2O4 or their chemical solid solution and physical mixed body; Also comprise high-molecular organic material, for example, tetrathio diphenylamines, poly-hexanedioic acid fourth two fat (PTMA:poly (2,2,6,6-tetramethylpiperidinyloxy-4-yl methacrylate) etc.

Each member of battery described in the utility model can stack by the order of anode ear, positive plate, barrier film, negative plate, negative electrode lug, negative plate, barrier film, positive plate, anode ear and constitute the laminated type battery; Also can stack by the order of negative plate, barrier film, positive plate, barrier film, reeling then constitutes the winding type battery core.

Described outer casing thickness not only can be realized ultra-thin, the flexible requirement of battery at 0.06～0.15mm, also is convenient to change the profile specification, simplifies production procedure, reduces production costs.

The utlity model has following beneficial effect:

(1) method of using the utility model to provide can be prepared ultrathin lithium ion battery, and its thickness is any numerical value between 0.3 to 3.0mm.Because between positive, negative electrode plate and barrier film, by colloidal electrolyte the three is bonded together, form an integral battery door core, rather than as the liquid flexible packing lithium ion electric pond, positive, negative electrode plate is to separate and loose (loose battery) with the barrier film three.Colloidal electrolyte described in the utility model has temperature stability preferably, and positive, negative electrode plate and the mutual bonding curing of barrier film three, changes less than 3%-20 ℃～+ 90 ℃ inner volumes.Therefore, press the ultra-thin battery of the utility model preparation, when ambient temperature changed, it is constant that cell thickness will keep, and can not expand.On the contrary, the liquid flexible packing lithium ion electric pond is in the said temperature scope, because the volumetric expansion of electrolyte, and the separating and loose compound mode of positive, negative electrode plate and barrier film three, cell thickness will rise with temperature, and huge variation take place, and obviously increases.

(2) battery can be according to installing needs, is bent and is out of shape.After in fitting into electronic apparatus, under external force, also can together crooked and distortion with electronic apparatus.

(3) most of materials of battery use are high-molecular organic materials, do not contain any toxic heavy metal in the battery, and for example: chromium, cadmium, lead and mercury etc. are the batteries of complete environmental protection.

This ultrathin type, flexible macromolecule lithium ion battery (or being called polymer Li-ion battery) are with a wide range of applications.For example:

(1) second generation bank card or credit card.First generation bank card is a passive type, by the personal information of the magnetic stripe memory card master on the card.Its shortcoming is that 1. personal information is stolen easily, and confidentiality is poor; 2. the magnetic stripe on the card damages easily and lost efficacy after repeated multiple times is swiped the card; 3. the end user must insert machine for punching the card with magnetic card, and the efficient low velocity is slow.Second generation bank card is active, and other parts such as battery, central processing element (CPU) and antenna are arranged, and is equivalent to a small computer, strong security, and information capacity is big, and is contactless, high efficiency, long service life.

(2) ultrathin toy power supply.

(3) portable health care/medical power supply.

(4) the remote control luggage used of airport security is followed the trail of label.

(5) military equipment and special device.

Description of drawings

Below in conjunction with embodiment and accompanying drawing the utility model is described in further detail:

Fig. 1 is the cross section structure schematic diagram of the utility model embodiment battery.Among the figure: aluminum-plastic composite membrane shell 11, plus plate current-collecting body 12, positive electrode coating 13, colloidal electrolyte 14, barrier film 15, negative electrode coating 16, negative current collector 17.

Fig. 2 is the positive electrode structural representation of the utility model embodiment battery.Among the figure: aluminium pole ears 21, CPP leakage preventing tape 22, aluminum foil current collector 23, electrode film 24.

Fig. 3 is the negative electrode structure schematic diagram of the utility model embodiment battery.Among the figure: nickel lug 31, CPP leakage preventing tape 32, Copper Foil collector 33, negative electrode plate 34.

Embodiment

Fig. 1, Fig. 2 and Figure 3 shows that embodiment of the present utility model, wherein shell 11 is the aluminum-plastic composite membrane bladder, is the aluminum-plastic composite membrane of being made up of multilayer polyethylene film, aluminium foil, polypropylene screen, polyamide membrane, its thickness is 0.09mm.At thickness is plus plate current-collecting body 12 surfaces of 0.016mm, applies positive electrode coating 13, and its thickness is 0.05mm.The positive electrode coating consist of cobalt acid lithium, conductive agent and binding agent, its percentage by weight proportioning is 93: 3: 4.The thick polyethylene of 0.02mm-propylene barrier film 15 is arranged between the positive and negative electrode sheet.On barrier film two surfaces, colloidal electrolyte layer 14 is arranged, its thickness extremely thin (can ignore too late), as film together with electrode film, negative electrode plate and diaphragm adhering.Negative electrode coating 16 is applied to negative electrode collector 17 surfaces that thickness is 0.0lmm for 0.045mm.The negative electrode coating consist of graphite powder, conductive agent and binding agent, its percentage by weight proportioning is 94: 1: 5.Use ultrasonic spot welder, anodal aluminium pole ears 21 is welded together with positive electrode current collector aluminium foil 23.By resistance spot weld, negative pole nickel lug 31 and negative electrode copper foil of affluxion body 33 are welded together.The battery gross thickness of preparing by embodiment of the present utility model is 0.32mm.

Claims (2)

1, a kind of ultrathin type, flexible macromolecule lithium ion battery, it is characterized in that: it mainly is made of four kinds of composite components:

1a, negative electrode composite component, it has the negative electrode coating to constitute negative electrode plate in the metal copper foil surface coated, and the nickel lug that coats with the CPP leakproof film is a negative wire;

1b, positive electrode composite component, it has the positive electrode coating to constitute electrode film in the metal aluminum foil surface coated, and the aluminium pole ears that coats with the CPP leakproof film is a positive wire;

1c, electrolyte composite component, it is provided with the gel state electrolyte layer in polyethylene-propylene barrier film both side surface, and described gel state electrolyte layer is bonded in the PE-PP membrane two sides respectively with negative electrode composite component and positive electrode composite component;

1d, shell, the aluminum-plastic composite membrane shell of forming by multilayer polyethylene film+aluminium foil+polypropylene screen+polyamide membrane;

Wherein, described negative electrode composite component, positive electrode composite component and electrolyte composite component constitute battery jointly, and described shell wraps described battery.

2, a kind of ultrathin type as claimed in claim 1, flexible macromolecule lithium ion battery is characterized in that: the thickness of battery is at 0.3 to 3.0 millimeter, and in-20 ℃～+ 90 ℃ temperature ranges, the battery change in volume is less than 3%.

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